It would be tough to overstate the level of cynicism that exists in certain corners of the Los Angeles establishment about the future of mass transit in Southern California. For many power brokers and longtime observers of the political scene, disparaging the chances of the region ever putting together a comprehensive transit system is some combination of rhetorical tic and parlor game.

In fact, the progress we've already made on a subway and light-rail network -- full of delays and misjudgments as it has been -- is remaking the physical and psychological terrain of Los Angeles in some profound ways. As more neighborhoods and landmarks are brought into transit's orbit, their relationship to the rest of the city and region shifts, giving us a powerful means of seeing the built environment with fresh eyes.

From that point of view, the opening on Sunday of the eight new Metropolitan Transportation Authority stations that make up the Gold Line extension -- six above ground and two below, reaching south and then east from Union Station into Little Tokyo, Boyle Heights and East Los Angeles -- is among the most significant civic milestones the city has reached in several years.

Design effects

The design of the new stops, overseen by architect Frank Villalobos and the firm AECOM, is in general more refined than the first stretch of the Gold Line, which opened in 2003 and in some stations delivers commuters directly into a narrow corridor squeezed between howling lanes of the 210 Freeway. But none is world-beating or likely to become a landmark in its own right.

A few show the pitfalls of earnestness, not to mention the deadening effect of endless design-review meetings at the bureaucratic and neighborhood level. (Does every station need to be a consensus-tested expression of community pride? I confess I'm not convinced.)

Among the above-ground stops in particular, less is definitely more: The stations that work best tend to be the ones that promote a fluid, easy connection between sidewalk and platform.

The real significance of the stations' debut on Sunday flows, instead, from the fact that with every substantial extension of the rail and subway network -- and this is a major one, with a price tag of $898 million, a large chunk of it to pay for 1.8 miles of underground tunneling -- another piece of the future Los Angeles comes startlingly into focus. More transit means more pedestrians, more people who pay attention to the shape and design of the city up close. That, in turn, means a growing constituency for shared space in Los Angeles and new interest in our long-neglected streetscapes and public sphere.

To put it another way: Transit and the life of the street are inextricably intertwined, and a boost to one is almost always a boost to the other.

At the same time, as trains trace new paths across the city, some of the divisions that for generations have made Los Angeles a balkanized collection of neighborhoods may begin to wobble or fall away.

That's not to say that some homogenization of L.A.'s various parts is on its way or should be our goal. Quite the opposite: New transit lines tend to throw the vibrant differences among neighborhoods into high relief.

Connecting a city

And yet they also promote a new sense of connectivity and fluidity in how we put the city and region together in our minds. In this case, by extending the Gold Line a mere six miles, Metro has woven new urban connections among downtown, Little Tokyo, the banks of the L.A. River, Boyle Heights and East Los Angeles.

The arts district has a different, arguably closer relationship with Little Tokyo. Commuters will better understand, simply by seeing this landscape out the train window, how improvements to Boyle Heights relate to plans to remake the banks of the river.

A similar batch of interrelationships will be forged each time Metro expands further: as the Expo Line moves south and west into Culver City and then Santa Monica, and as the Gold Line's Foothill Extension stretches east through the San Gabriel Valley. The fact that the underground section of the Gold Line was built without incident or cost overruns may help tamp down lingering doubts about the logistics of building the Subway to the Sea extension west along Wilshire Boulevard.

After Villalobos and AECOM handled the preliminary architecture of the new stations, each one was then handed off for final design to a separate architect-artist team. The standout designs are the two at the eastern end of the extension.

The Atlantic Station, by AECOM architects Todd Osborne and Russell McCarley and the artist group Adobe L.A., pairs a series of sail-like canopies with colored-cement benches and a lacquered, floridly painted robot sculpture at its western entrance.

The East L.A. Civic Center station, by Villalobos with artist Clement Hanami, suggests a row of blooming poppies and adds a burst of bright color to its stretch of 3rd Street.